Bibcode
DOI
Knapen, J. H.; Shlosman, I.; Heller, C. H.; Rand, R. J.; Beckman, J. E.; Rozas, M.
Referencia bibliográfica
The Astrophysical Journal, Volume 528, Issue 1, pp. 219-235.
Fecha de publicación:
1
2000
Revista
Número de citas
57
Número de citas referidas
48
Descripción
We present high angular and velocity resolution two-dimensional
kinematic observations in the spectral lines of Hα and CO
J=1-->0 of the circumnuclear starburst region in the barred spiral
galaxy M100, and compare them with kinematics derived from our
previously published numerical modeling. The Hα data, fully
sampled and at subarcsecond resolution, show a rotation curve that is
rapidly rising in the central ~140 pc, and stays roughly constant, at
the main disk value, further out. Noncircular motions are studied from
the Hα and CO data by detailed consideration of the velocity
fields, residual velocity fields after subtraction of the rotation
curve, and sets of position-velocity diagrams. These motions are
interpreted as the kinematic signatures of gas streaming along the inner
part of the bar, and of density wave streaming motions across a
two-armed minispiral. Comparison with a two-dimensional velocity field
and rotation curve derived from our 1995 dynamical model shows good
qualitative and quantitative agreement for the circular and noncircular
kinematic components. Both morphology and kinematics of this region
require the presence of a double inner Lindblad resonance in order to
explain the observed twisting of the near-infrared isophotes and the gas
velocity field. These are compatible with the presence of a global
density wave driven by the moderately strong stellar bar in this galaxy.
We review recent observational and modeling results on the circumnuclear
region in M100, and discuss the implications for bar structure and gas
dynamics in the core of M100 and other disk galaxies.